Test edition conflict, parallel edition w/o conflict and removal conflict.

3 simple text files are created on one VM and it waits until the other one
to be synced. Thus the test starts. Each test changes the same file
simultaneously on both VMs.

* Edition conflict test change the same line differently on each VM.
It aims to test a conflict detection.
* Parallel edition test change different lines on each VM.
It aims to test if there is merge support.
* Removal conflict test change a line on one VM and remove the file on the
another one.
It aims to test a conflict detection.
Change the max file number test to be faster to sync.

1000 files per directory. Without it the syncing is too slow.